Graphs showing improper data?

To provide some context, I'm trying to create a network monitoring device using a Raspberry Pi that communicates with Google Analytics for a senior project. My Raspberry Pi has multiple scripts running TCP Dump that then uses PyCurl to send Google Analytics data. In short the scripts count the number of packets for each different protocol and then send that number to Google Analytics in the form of events.

The communication between the Raspberry Pi and Google Analytics seems to be fine as the Real-Time graph is showing all of the events for each individual protocol that I'm sending. However, in my custom dashboard, the graphs are acting strange. They seem to all be capping out at 500 total events for an entire day then dropping down to 0 events for the next day. The third day then shows data but caps at 500 again with the fourth day going back to 0. It keeps doing this same pattern even though the Real-Time events graph is showing data for all four days with each protocol having more than 1,000 events each day. The graphs are set to look at Total Events and they're separated for each protocol by filtering Event Labels. This way each protocol gets its own graph. They are all doing this same pattern of 500, 0, 500, etc.

I'm unsure what the problem is. Am I sending too much data to Google Analytics that makes it unable to keep up? Does Google Analytics think I'm spamming? Do I need some sort of premium service to show more than 500 events on a graph? Any information would be extremely helpful. Thank you in advance!